1. Field of the Invention
The present invention relates to a multi-way input device capable of operating a plurality of electric components at a time by operation of an operating shaft.
2. Description of the Related Art
A conventional multi-way input device is constructed as in FIGS. 11 to 13, in which a first interlocking member 31 curved in an arch shape is disposed in the interior of a frame 30, the frame 30 being formed in the shape of a box having side plates and which is open on its lower side. The first interlocking member 31 has mounting portions 31a formed respectively at both ends thereof. The mounting portions 31a are fitted respectively into holes 30c and 30a formed in side plates of the frame 30, whereby the first interlocking member 31 is mounted rotatably in the interior of the frame 30.
A hole 34 is formed in an end face of each mounting portion 31a and a rotary shaft 33 of a variable resistor 32 comes into engagement with the hole 34. Further, a slit 35 is formed longitudinally in the arched portion of the first interlocking member 31.
Below the first interlocking member 31 is disposed a second interlocking member 40 in a direction perpendicular to the first interlocking member. The second interlocking member 40, which is formed of a metallic material such as a die casting alloy, is centrally provided with a spherical body 41 and is also provided with right and left arm portions 42 extending horizontally from the spherical body 41, with circular mounting portions 42a being projectingly formed respectively at the tips of the arm portions 42. The mounting portions 42a are inserted respectively into holes 30b and 30d formed in the frame 30, whereby the second interlocking member 40 is mounted rotatably in the interior of the frame 30.
A hole 43 is formed in an end face of each mounting portion 42a and the rotary shaft 33 of another variable resistor 32 is press-fitted into the hole 43.
A slot 45 is vertically formed centrally through the spherical body 41. The first and second interlocking members 31, 40 are disposed in such a manner that the respective slit 35 and slot 45 intersect each other perpendicularly.
An operating shaft 36 is inserted through the slot 45 of the second interlocking member 40. The operating shaft 36, which is formed of a metal for example, takes a shape such that an oval-shaped support portion 38 is formed centrally and upper and lower support rods are integral with the support portion 38. A disc-like spring shoe 47 integral with the operating shaft 36 is formed at a position close to a lower end portion 36a of the operating shaft 36 projecting downward.
A small hole 39 is formed in the support portion of the operating shaft 36. The hole 39 is aligned with a hole 44 formed sideways of the second interlocking member 40 and a round pin 46, which is constituted by a metallic rod for example, is inserted or press-fitted into the thus-aligned holes 39 and 44 and is caulked at both ends thereof, whereby the operating shaft 36 is mounted tiltably to the second interlocking member 40.
The operating shaft 36 extending upward from the support portion 38 is inserted through the slit 35 of the first interlocking member 36. By tilting the operating shaft 36 along the slit 35 of the first interlocking member 31, the second interlocking member 40 can be rotated with its mounting portions 42a as fulcrums. A knob 55 is fixed to the upper end of the operating shaft 36 which extends upward from the slit 35.
An operating member 37, which is formed dish-like in external form using a resin material for example, is secured to the lower end portion 36a of the operating shaft 36. A boss portion 37a is centrally projected on the operating member 37 and the end portion 36a of the operating shaft 36 is inserted into a bore 50 formed through the boss portion 37a so that the operating member 37 can move vertically.
A bottom plate 49 is mounted so as to cover the lower opening of the frame 30. In this state, the operating member 37 is in elastic contact with the bottom plate 49.
By tilting the operating shaft 36 along the slot 45 of the second interlocking member 40 with the round pin 46 as a fulcrum, the first interlocking member 31 can rotate with its mounting portions 31a as support shafts. Likewise, by tilting the operating shaft 36 along the slit 35 of the first interlocking member 31, the second interlocking member can rotate with its mounting portions 42a as support shafts.
The rotary shafts 33 of the variable resistors 32 locked to side plates of the frame 30 are press-fitted in the holes 34 and 43 of the first and second interlocking members 31 and 40 so that both interlocking members and the variable resistors operate integrally with each other.
A generally conical return spring 48 is stretched between the spring shoe 47 of the operating shaft 36 and an inside bottom of the operating member 37. With the biasing force of the return spring 48 the operating member 37 is brought into elastic contact with the bottom plate 49, whereby the operating shaft 36 can be held in an upright neutral state.
The operation of the conventional multi-way inpout device will now be described. First, as shown in FIG. 12, the upper end of the operating shaft 36, when not in operation, projects upright from a hole 56 formed in a top plate of the frame 30 and the operating member 37 is kept in elastic contact with the bottom plate 49 in a horizontal state by means of the return spring 48, so that the operating shaft 36 is in an upright neutral state.
In this state, as shown in FIG. 13, by tilting the operating shaft 36 rightward in a clockwise direction along the slot 45 of the second interlocking member 40, the first interlocking member 31 is rotated, whereby the variable resistor 32 is operated and hence the resistance value thereof can be changed.
As a result of the tilting motion of the operating shaft 36, the operating member 37 tilts as in FIG. 13 and a part of the peripheral edge of the thus-tilted operating member 37 moves in sliding contact with the surface of the bottom plate 49. Consequently, the operating member 37 moves toward the circular spring shoe 47, thereby causing the return spring 48 to be compressed and deflected.
Upon release of the operating force applied to the operating shaft 36, the operating member 37 which has been tilted comes to move in sliding contact with the surface of the bottom plate 49 with the biasing force of the return spring 48. The operating member 37 gradually comes to moves horizontally with respect to the bottom plate 49 and in this way the operating shaft 36 reverts automatically to its upright neutral state shown in FIG. 12.
For operating the variable resistor 32 engaged with an arm portion 42 of the second interlocking member 40, the operating shaft 36 is tilted along the slit 35 of the first interlocking member 31, whereby the second interlocking member 40 is rotated and this rotation permits the variable resistor 32 to operate and change its resistance value.
In the above conventional multi-way input device, however, since the operating shaft 36 is pivotally supported through the round pin 46 by the second interlocking member 40, the number of parts used is large.
Besides, the work of inserting or press-fitting the round pin 46 into the second interlocking member 40 and caulking both ends thereof to prevent dislodgment is needed and therefore the assembling work for the conventional multi-way input device is so much complicated.